Like you said, Crash Bandicoot 1 PAL-UK BL is going to be really hard to find!
I don't think there's even confirmation that it came with a factory seal? I've only seen pics of it in shrinkwrap with a HMV sticker.
It's not high on my priority list at the moment so I'll hunt it down sometime in the future, although if one came up in the meantime I'd pounce on it pretty quick